Haines D E, Whitworth R H
J Comp Neurol. 1978 Nov 1;182(1):137-50. doi: 10.1002/cne.901820109.
Efferent projections from the paraflocculus of the tree shrew (Tupaia glis) were studied utilizing the Fink and Heimer ('67) method. Cerebellar corticonuclear fibers of both dorsal (Dpf) and ventral (Vpf) divisions of the paraflocculus terminate in the lateral cerebellar nucelus (NL) and in the posterior interposed nucleus (NIP). These fibers are ipsilateral, topographically organized and arranged into at least two zones. Following injury to either the Dpf or Vpf, degenerated axons are found in lateral and caudal regions of the NIP respectively. Consequently, these two portions of the paraflocculus have relatively exclusive terminal fields with overlap only at the periphery. Preterminal debris is seen in basically similar areas of the NL (caudolateral, caudal, ventral) after damage to either the Dpf or Vpf. This observation leads to the conclusion that the terminal fields for these areas of parafloccular cortex are largely coextensive in the NL. In addition to the topographical representation of the Dpf and Vpf in both the NL and NIP, there is evidence that these corticonuclear fibers are also organized into the general zonal pattern hypothesized by Voogd ('69). Persistent and numerous degenerated axons from both the Dpf and Vpf end in lateral and caudal NIP, respectively, corroborating the presence of a relatively wide zone C2 in both divisions of the paraflocculus. The Dpf and Vpf also project into the NL to a terminal field that appears to consist of two portions. One part located in caudal, ventral and/or caudoventral areas of the NL and a second at slightly more rostral and rostrolateral areas. The presence of a cortical region which is affiliated with two areas of the NL substantiates not only the existence of zone D in the paraflocculus, but gives experimental evidence that it may consist of two parts as previously suggested (Voogd, '69). From the Dpf many fibers enter the NL while few are seen in this nucleus after damage to the Vpf. This suggests that zone D is wider in the Dpf and narrower in the Vpf. The results of this study do not support previous suggestions that the paraflocculus projects to either only the NL or to most of, or all of, the ipsilateral cerebellar nuclei. No projections to any contralateral cerebellar nuclei are seen. There is also no conclusive proof that the parafloccular cortex of Tupaia projects into the vestibular complex or to any other brainstem relay nuclei.
利用芬克和海默（1967年）的方法，对树鼩（笔尾树鼩）小脑旁绒球的传出投射进行了研究。小脑旁绒球背侧（Dpf）和腹侧（Vpf）分区的小脑皮质核纤维终止于小脑外侧核（NL）和后间位核（NIP）。这些纤维是同侧的，呈拓扑组织，并至少排列成两个区域。在Dpf或Vpf受损后，分别在NIP的外侧和尾侧区域发现变性轴突。因此，小脑旁绒球的这两个部分具有相对独立的终末野，仅在周边有重叠。在Dpf或Vpf受损后，在NL的基本相似区域（尾外侧、尾侧、腹侧）可见终末前碎片。这一观察结果得出结论，小脑旁绒球皮质这些区域的终末野在NL中基本是共延的。除了在NL和NIP中Dpf和Vpf的拓扑表示外，有证据表明这些皮质核纤维也按照沃格德（1969年）假设的一般区域模式进行组织。来自Dpf和Vpf的持续且大量的变性轴突分别终止于NIP的外侧和尾侧，证实了小脑旁绒球两个分区中相对较宽的C2区的存在。Dpf和Vpf也投射到NL的一个终末野，该终末野似乎由两部分组成。一部分位于NL的尾侧、腹侧和/或尾腹侧区域，另一部分位于稍靠前和 rostrolateral 区域。与NL的两个区域相关联的皮质区域的存在不仅证实了小脑旁绒球中D区的存在，而且提供了实验证据，表明它可能如先前所建议的（沃格德，1969年）由两部分组成。从Dpf有许多纤维进入NL，而在Vpf受损后在该核中很少见到纤维。这表明D区在Dpf中较宽，在Vpf中较窄。本研究结果不支持先前的观点，即小脑旁绒球仅投射到NL或同侧小脑核的大部分或全部。未观察到向任何对侧小脑核的投射。也没有确凿证据表明笔尾树鼩的小脑旁绒球皮质投射到前庭复合体或任何其他脑干中继核。
